The invention relates to power drilling and pulling devices, e.g., for vertical insertion and withdrawal of well points, posts and the like.
Well points, or well pipes, are inserted into the ground, e.g. for depths up to about 25 feet, where the water table is close to the surface. Groundwater enters a well point through perforations in a tip region, and is removed by means of a pump. One or a few well points may be used for supplying water for consumption in suitable locations. The invention is particularly addressed to well points employed in numbers, e.g., about construction sites, along the paths of underground sewer lines, concrete channels, designated building lots, excavation for laying concrete or pipelines, or anywhere it is desired to remove groundwater to temporarily lower the water table to permit excavation and installation of pipes or equipment. When the need has ended, e.g., upon completion of a project, the well points are removed from the ground for use at the next site. In order to avoid the pipes becoming jammed in the ground, it is important that force be applied to the well point axially, i.e. vertically in the usual situation, as it is withdrawn. Also, it is advantageous to be able to pull more than one well point without having to move the entire pulling apparatus each time to another location.